code: def setup_method(self):
      self.A = np.array([[1, 2, 3], [4, 5, 6]])
      self.B = np.array([[1, 2], [3, 4], [5, 6]])
      self.C = np.array([[1, 2], [3, 4]])
  
imports: from functools import partial
  from itertools import product
  import operator
  from pytest import raises, warns
  from numpy.testing import assert_, assert_equal
  import numpy
  import scipy.sparse
  import scipy.sparse.linalg._interface
  from scipy.sparse._sputils import matrix
label_desc: Use image node_id 1 for calling the TestLinearOperator obj's underlying member method code with example usage: obj.setup_method() without return types